Help! My ft explorer couldn't fly help!

[starletzzang]

I tested the ft explorer for the first time today, but couldn't fly.

After full throttle, the moment I threw the aircraft with my standing hand, the aircraft leaned toward the ground and fell to the ground.

The weight in ft is about 490g without battery, but my aircraft weighs about 800g without battery, so it's about 2 pounds heavy, so is it flying and sitting down?
And it fell from a low height to the side, and the wing was split in two. The wing is definitely weaker than the ft simple cub.

What could be the reason for not being able to fly?

First, it is heavy.
Second, wrong motor and prop selection. Third, the center of the muguet does not match.
Is there any other reason?


Motor a2212 13t 1000kv
Prop 8x4.5 sf
30a esc
1300mag 3s battery 110g
9g servo

 

[JasonK]

given your plane was about 2x the weight, I would expect it to need quite a bit more speed to get enough lift to stay airborne. (so a soft throw wouldn't have got enough initial airspeed to get sufficient control on the control surfaces to keep it stable)

- Did you have the numbers on your prop facing the front of the plane? (if not, you were getting way less thrust then you should have)
- Did it roll as it fell down? did you have your fingers on the controls to keep the wing level as it launched?

it sounds like your CG didn't match the recommend CG, that alone could cause it to crash.

The wing on the FT Explorer is fairly big and I have heard that aggressive flying can fold it and that a spar reinforcing it in the middle would help, however unless it folded before you hit the ground, that is not like any issue with it not flying, just it not taking a crash as well as the other plane.

other reasons could be a bad launch (slow, wrong angle, imparting roll, pitch, yaw into the plane, etc), throwing it with the wind instead of into the wing, control system issue, etc, etc. The possible list is very long. The goal in troubleshooting a bad launch is to try to figure out the most likely cause(s) and correct them.

 

[Matthewdupreez]

mine came in at 1000grams with a battery... and it flew on a C power pack... with a 1045 prop...
i also reinforced the wing with an aluminum spar, as it folded on my first flight...
i would recommend using a aluminium / carbon/ fibre glass, or wood spar in the wing to reinforce it.... and yes, as @JasonK said, give it a good fast throw.... also if you can throw it from a height... eg a roof/table/chair/ladder.... as mine would drop about 1.5m before starting to fly

 

[JasonK]

If you dropping 1.5m before it gets enough lift, then something is off. I would consider .5m of drop concerning

 

[CappyAmeric]

It looks like it was way too heavy, so I am assuming you used some other kind of foamboard - that would also make it likely under powered and the CG would be off if over weight. Contributing was likely a shortened fuselage which shifted CG as well as limiting pitch authority.

The FT Explorer is a good flier, so now that you have the build experience, I would recommend you get an actual speed build kit so you can more closely replicate the flying experience: https://store.flitetest.com/ft-explorer-wr-1447mm/

 

[Matthewdupreez]

If you dropping 1.5m before it gets enough lift, then something is off. I would consider .5m of drop concerning

because it was ridiculously heavy.... i am planning to re build it and see how that goes

 

[starletzzang]

mine came in at 1000grams with a battery... and it flew on a C power pack... with a 1045 prop...
i also reinforced the wing with an aluminum spar, as it folded on my first flight...
i would recommend using a aluminium / carbon/ fibre glass, or wood spar in the wing to reinforce it.... and yes, as @JasonK said, give it a good fast throw.... also if you can throw it from a height... eg a roof/table/chair/ladder.... as mine would drop about 1.5m before starting to fly

Can you tell me in detail how you reinforced it with spar?

 

[AIRFORGE]

mine came in at 1000grams with a battery... and it flew on a C power pack... with a 1045 prop...
i also reinforced the wing with an aluminum spar, as it folded on my first flight...
i would recommend using a aluminium / carbon/ fibre glass, or wood spar in the wing to reinforce it.... and yes, as @JasonK said, give it a good fast throw.... also if you can throw it from a height... eg a roof/table/chair/ladder.... as mine would drop about 1.5m before starting to fly

What did you do to get a 10 prop on it? Stock design fits a max of an 8 or 8.5 prop. I made mine an A-tail Bronco.

 

[Matthewdupreez]

What did you do to get a 10 prop on it? Stock design fits a max of an 8 or 8.5 prop. I made mine an A-tail Bronco.

i shoved the ply motor mount as far up as it would go in the foam holder..... it just barely had clearance.... i'm talking like 1mm clearance

 

[Matthewdupreez]

Can you tell me in detail how you reinforced it with spar?

well, i was using the trainer wing, so i wanted dihedral in the middle...
so i got an 80cm long piece of aluminum "angle iron" marked the center of it and clamped it in my vice...
with the mark just on the one side of the vice....
took a hammer, and smacked it until i had the desired bend in it for the dihedral... then i sanded it with 40grit sandpaper....to get the glue to stick nicely....
then cut the wing in half where they join.
cover half of the spar with hot glue... slide it in in front of the foam spar, with the 2 flat pieces against the foam spar and the base the wing.... make sure your spar is going at the correct angle.... you don't want to have anhedral....hold for 1 minute..
do on other half of spar, and hold for 1 minute.... wing is done

 

[cbf123]

What kind of foam are people using to make it that much heavier than the plans?

I know that some of the "Elmer's" brand foamboard is way heavier. The "Ross" branded stuff used to be just a little heavier than the Adams Readi-board, but I heard one report that it's recently gotten heavier.

The plans assume the use of the Adams foamboard, making it heavier will require a faster launch and will result in a faster stall speed, so not as friendly to someone who's new to flying.

 

[Matthewdupreez]

What kind of foam are people using to make it that much heavier than the plans?

I know that some of the "Elmer's" brand foamboard is way heavier. The "Ross" branded stuff used to be just a little heavier than the Adams Readi-board, but I heard one report that it's recently gotten heavier.

The plans assume the use of the Adams foamboard, making it heavier will require a faster launch and will result in a faster stall speed, so not as friendly to someone who's new to flying.

I use insulation foam...

 

[dave1up]

Try not to use hot glue - its heavy. Try gorilla glue.

 

[Matthewdupreez]

Try not to use hot glue - its heavy. Try gorilla glue.

yea... im gonna use tiny dots of hot glue, to hold everything together, and then use wood glue for the rest.

 

[dave1up]

i use polyurethane glue, it foams up & fill joints & is light.

 

[starletzzang]

g 3s 배터리 110

당신의 비행기가 무게의 약 2배였다는 점을 감안할 때, 나는 그것이 공중에 머물기에 충분한 양력을 얻기 위해 훨씬 더 빠른 속도가 필요할 것으로 예상합니다. (그래서 부드러운 던지기는 안정을 유지하기 위해 조종면을 충분히 제어할 수 있을 만큼 초기 속도가 충분하지 않았을 것입니다)

- 비행기 정면을 향하도록 소품에 숫자가 있었나요? (그렇지 않다면, 당신은 훨씬 더 적은 추진력을 얻었어야 했습니다)
- 넘어지면서 굴러갔나요? 그것이 발사될 때 날개 높이를 유지하기 위해 컨트롤에 손가락을 댔습니까?

귀하의 CG가 권장 CG와 일치하지 않는 것 같으며, 그것만으로도 충돌이 발생할 수 있습니다.

FT 익스플로러의 날개는 상당히 커서 공격적인 비행으로 접을 수 있고 중간에 날개를 보강하는 것이 도움이 된다고 들었습니다. 그러나 땅에 떨어지기 전에 접히지 않으면 아무 문제가 되지 않습니다. 다른 비행기와 마찬가지로 충돌을 일으키지 않을 뿐입니다.

다른 이유는 잘못된 발사(느림, 잘못된 각도, 롤, 피치, 요잉을 비행기로 전달하는 등), 날개 대신 바람과 함께 던지는 것, 제어 시스템 문제 등일 수 있습니다. 가능한 목록은 매우 긴. 잘못된 실행 문제를 해결하는 목표는 가장 가능성이 높은 원인을 파악하고 해결하는 것입니다.[/인용]


thanks very much!